The best way to eliminate this issue going forward is to replace custom settings with custom metadata. Custom metadata allows the developer to define custom configuration data that can be used by the Apex code. Custom metadata records are also deployed as part of the metadata, which means they are automatically available in the sandboxes after refresh. Custom settings, on the other hand, are not deployed as part of the metadata, which means they need to be manually created or imported in the sandboxes after refresh. Setting the setting type on the custom setting to List or Hierarchy will not solve this issue, as the custom setting records will still not be deployed. Replacing custom settings with static resources will not work, as static resources are not meant to store configuration data and cannot be accessed by Apex code easily. Reference: [Custom Metadata Types], [Custom Settings], [Apex Developer Guide]